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Why is my propeller not running? — Parallax Forums

Why is my propeller not running?

Hello people, I have a problem here, and although somehow my P8X32A propeller can not be programmed. I use the SimpleIDE, as a serial port I use the CP2102 (This contains DTR and RTS). As operating voltage, the chip runs at 3.3V.

On my oscilloscope I see that the RESET pin is pulled to ground. But nevertheless, SimpleIDE tells me that no propeller was found.

On the propeller itself, I have no EEPROM connected, as I understand it, he can also run code in RAM. I tried it with and without 12Mhz Crystal. It does not work at all: /
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Comments

  • I believe the reset pin should be pulsed to ground, are you holding it down permanently? Looking on the PropPlug schematic it shows a capacitively coupled inverter using DTR to generate Reset.
  • Here is my circuit. The reset pin is not permanently on ground, the cp2102 pulls the pin to ground when programming.
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  • mcuOne wrote: »
    the cp2102 pulls the pin to ground when programming.

    Just to double check here, the reset pin should be pulled to ground (pulsed as Hal said), momentarily before programming starts. It cannot be held to ground during programming.

    Holding reset low effectively holds the Propeller in a disabled state in which it cannot be programmed, or do anything else.

  • mcuOnemcuOne Posts: 16
    edited 2018-09-04 19:15
    This is how it looks on the reset pin on the oscilloscope when I want to program the propeller. Looks strange. Especially the spikes.

    VonSzarvas wrote: »
    mcuOne wrote: »
    the cp2102 pulls the pin to ground when programming.

    Just to double check here, the reset pin should be pulled to ground (pulsed as Hal said), momentarily before programming starts. It cannot be held to ground during programming.

    Holding reset low effectively holds the Propeller in a disabled state in which it cannot be programmed, or do anything else.


    No, the reset pin is not permanently to ground, only if i programming, then the cp2101 pull down the reset pin to ground in pulse.
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  • Ok, on my cp2101 stick was a capacitor in front of it, this also explains the spike. Have the capacitor removed and soldered a bridge. When Reset is pulled to Ground while programming, the pulse looks like this. Ok, on my cp2101 stick was a capacitor in front of it, this also explains the spike. Have the capacitor removed and soldered a bridge. When Reset is pulled to Ground while programming, the pulse looks like this.

    It is grounded 25ms, is that too long?
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  • This this configuration
  • Are the batteries low ??
  • DigitalBob wrote: »
    This this configuration

    Thanks.

    Ok, I have the propeller running, with the Propeller Tool. It still does not work with the PropellerIDE and the SimpleIDE. Is there anything to consider in the settings in the SimpleIDE? As I said, I have no EEPROM and Crystal connected.
  • VonSzarvasVonSzarvas Posts: 3,273
    edited 2018-09-04 21:10
    mcuOne wrote: »
    It is grounded 25ms, is that too long?

    Not too long.

    The reset pulse can be a low as 1uS, and as long as <50mS (as I recall)

    There is a window of 100mS from when the reset is triggered in which you need to start uploading code to the Propeller, otherwise it will attempt to boot from EEprom, and if that fails will shutdown.

    Ie. send your reset pulse and then start uploading code immediately.


    Edit: Found this old post that explains the reset parameters some more: https://forums.parallax.com/discussion/comment/1172416/#Comment_1172416
  • Ok, I have the propeller running, with the Propeller Tool.

    When this worked how was the RESET pin of the propeller IC connected to the CP2102 module? Was it to the DTR pin or the RTS pin?
  • tw1 wrote: »
    Ok, I have the propeller running, with the Propeller Tool.

    When this worked how was the RESET pin of the propeller IC connected to the CP2102 module? Was it to the DTR pin or the RTS pin?

    The DTR pin is connected to the propeller
  • And this is my configuration in SimpleIDE and Propeller Tool
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  • tw1tw1 Posts: 13
    edited 2018-09-04 21:57
    Thank you.

    It might be worth comparing with your scope the output of the DTR pin when using Propeller Tool and when using PropellerIDE and SimpleIDE.
  • Propeller Tool: 26,29ms Pull Down
    SimpleIDE: 25,67ms Pull Down
    Propeller IDE: 19,34ms Pull Down

    So it's a minimal difference, so I do not think that's what it's about.
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  • RaymanRayman Posts: 13,805
    You might want to add a 10uF between VCC and gnd somewhere close to Prop, if you don't have one already...
  • Rayman wrote: »
    You might want to add a 10uF between VCC and gnd somewhere close to Prop, if you don't have one already...

    I tried, does not bring anything.
  • When you set up the program with SimpleIDE and an Activity board the board configuration file tries to set the CPU clock to 80MHz using a 5MHZ crystal, your 12MHZ crystal will try to have the system clock going at 192MHz, somewhat beyond the specs of a Propeller 1. I'm not sure how the Propeller will react when you specify an Activity board but no crystal.
  • But you can program the Propeller without external Crystal in the SimpleIDE or?
  • I can't see any ground between the Propeller and your cp2102 in your Fritzing.
  • Thank you.

    I have just put a propeller (with bypass capacitors) on a breadboard and connected DTR directly to the propeller RESET. Using PropellerIDE I can blink an LED with or without a 5MHz crystal. The difference between our circuits might be the bypass capacitors.
    Rayman wrote: »
    You might want to add a 10uF between VCC and gnd somewhere close to Prop, if you don't have one already...

  • frida wrote: »
    I can't see any ground between the Propeller and your cp2102 in your Fritzing.

    Sorry I forgot part in fritzing ^ ^ but everything is connected correctly.
    tw1 wrote: »
    Thank you.

    I have just put a propeller (with bypass capacitors) on a breadboard and connected DTR directly to the propeller RESET. Using PropellerIDE I can blink an LED with or without a 5MHz crystal. The difference between our circuits might be the bypass capacitors.
    Rayman wrote: »
    You might want to add a 10uF between VCC and gnd somewhere close to Prop, if you don't have one already...

    Ok, does this work for you also in the SimpleIDE?
  • When I load and run your program on my Project Board USB, which has a removable crystal, the simple hello program you show runs just fine, when I remove the crystal the program appears to download (blinking red and blue leds by the FTDI chip) but the program fails. It won't even open the terminal screen. Even using an RCslow or RCfast board the program fails, probably because the chip can't generate the 115,200 baud rate for the serial terminal.
  • So that means that I can not program the propeller without external Crystal in the SimpleIDE?
    Hal Albach wrote: »
    When I load and run your program on my Project Board USB, which has a removable crystal, the simple hello program you show runs just fine, when I remove the crystal the program appears to download (blinking red and blue leds by the FTDI chip) but the program fails. It won't even open the terminal screen. Even using an RCslow or RCfast board the program fails, probably because the chip can't generate the 115,200 baud rate for the serial terminal.

  • I use Spin and PASM with the PropellerIDE and have no experience with SimpleIDE. However, to make my spin program run without a crystal I set _CLKMODE = RCFAST.
  • RaymanRayman Posts: 13,805
    There was a time when we sometimes had to go into device manager and change a usb serial port setting to make things work...
    Can't remember what we had to change, but maybe it was the "Latency Timer"...

    Anyway, I'd reboot and try again...
  • Ok, PropellerIDE works now even after I put a 10uf capacitor on VCC and GND. Simple IDE still does not work.
  • What is your test program for SimpleIDE?
  • When you say SimpleIDE doesn't work, are you getting any error messages? Which icon in SimpleIDE are you using to download the program?
  • tw1 wrote: »
    What is your test program for SimpleIDE?

    This is a example program:
    #include "simpletools.h" // Include simple tools

    int main() // Main function
    {
    print("Hello!"); // Display test message
    }

    And the error Message is:
    Opening file 'cmm/Welcome.elf'
    ERROR: Download failed: -1
    Hal Albach wrote: »
    When you say SimpleIDE doesn't work, are you getting any error messages? Which icon in SimpleIDE are you using to download the program?
  • Does SimpleIDE find your Propeller chip?

    You'd see it listed in the com port drop-down if it did. Near the top right.

    Also.. I seem to recall SimpleIDE and PropellerIDE don't always share com-ports well. In case that's relevant for you, try closing all other IDE's when testing SimpleIDE?
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